Limit (cos(1\x))|tan x| x-> .5pi

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Homework Statement


having a hard time figuring out. I know the answer if infinite but having a hard time proving it

Homework Equations


tan x = cot (.5pi - x) did not help


The Attempt at a Solution


tried substituting t = 1\x got stuck

thanks
 
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The limit as x goes to what?
 
x goes to (pi)(1\2)

pi 3.14...
 
limx→π/2cos(1/x) exists, so what's left is limx→π/2|tan x|, which is infinite.
 
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